Attempts have been made to make lead grid arrays by forming numerous leads at spaced locations on a metal sheet and bending the leads using a punch and die before attaching them to the components to be connected as shown, for example, in U.S. Pat. Nos. 5,420,461 and 5,210,939.
As disclosed, for example, in certain preferred embodiments of U.S. Pat. Nos. 5,518,964 and 5,798,286, the disclosures of which are hereby incorporated by reference herein and copies of which are annexed hereto, microelectronic components incorporating flexible leads can be made by a process in which the leads are connected between opposing elements and the opposing elements are moved away from one another so as to bend the leads through a controlled displacement. For example, in some embodiments taught by these patents, leads extend along the bottom surface of a dielectric connection component. Each lead has a terminal end connected to a metallic terminal which holds the terminal end of the lead in place. Each lead also has a tip end, remote from the terminal end, which is releasably held on the bottom surface of the dielectric element. The dielectric element is juxtaposed with another element, such as a semiconductor chip, wafer or additional connection component. The tip ends of the leads are bonded to contacts on the opposing element. The elements are then moved away from one another thereby detaching the tip end of each lead from the dielectric element and bending each lead to a vertically extensive disposition. A flowable material such as a curable dielectric liquid may be injected into the space between the leads during or after the movement step and cured to form a compliant dielectric layer surrounding the leads.
Numerous other variations and adaptations of the basic principles taught in these patents are also possible. For example, disclosed in co-pending, commonly assigned U.S. Provisional Patent Application No. 60/077,928, the disclosure of which is hereby incorporated by reference herein, the leads may be connected to one or another of the elements through frangible sections so that after the moving step, the frangible sections break leaving ends of the leads exposed at a surface of the dielectric layer formed from the encapsulant. Such a process can be used, for example, to fabricate test fixtures. As disclosed, for example, in co-pending, commonly assigned U.S. patent application Ser. Nos. 08/366,236, filed Dec. 29, 1994 and 08/989,312, filed Dec. 12, 1997, the disclosures of which are hereby incorporated by reference herein, one or another of the elements may include a metallic plate which is etched after the moving step to form terminals connected to the leads. However despite these and other advances in the art, still further variations would be desirable.